time-to-botec/js/node_modules/@stdlib/ndarray/base/strides2order/README.md

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@license Apache-2.0
Copyright (c) 2018 The Stdlib Authors.
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# strides2order
> Determine the order of a multidimensional array based on a provided stride array.
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## Usage
```javascript
var strides2order = require( '@stdlib/ndarray/base/strides2order' );
```
#### strides2order( strides )
Determines the order of a multidimensional array based on a provided stride array.
```javascript
var order = strides2order( [ 2, 1 ] );
// returns 1
order = strides2order( [ 1, 2 ] );
// returns 2
order = strides2order( [ 3 ] );
// returns 3
order = strides2order( [ 1, 3, 2 ] );
// returns 0
order = strides2order( [] );
// returns 0
```
The function returns one of the following values:
- `1`: based on the stride array, the array is in row-major order.
- `2`: based on the stride array, the array is in column-major order.
- `3`: based on the stride array, the array is in both row-major and column-major order.
- `0`: based on the stride array, the array is in neither row-major nor column-major order.
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## Examples
<!-- eslint no-undef: "error" -->
```javascript
var discreteUniform = require( '@stdlib/random/base/discrete-uniform' );
var shape2strides = require( '@stdlib/ndarray/base/shape2strides' );
var randu = require( '@stdlib/random/base/randu' );
var strides2order = require( '@stdlib/ndarray/base/strides2order' );
var strides;
var order;
var shape;
var i;
var j;
shape = [ 0, 0, 0 ];
for ( i = 0; i < 20; i++ ) {
// Generate a random array shape:
shape[ 0 ] = discreteUniform( 1, 10 );
shape[ 1 ] = discreteUniform( 1, 10 );
shape[ 2 ] = discreteUniform( 1, 10 );
// Compute the strides:
if ( randu() < 0.5 ) {
strides = shape2strides( shape, 'row-major' );
} else {
strides = shape2strides( shape, 'column-major' );
}
j = discreteUniform( 0, shape.length-1 );
strides[ j ] *= ( randu() < 0.5 ) ? -1 : 1;
// Determine the order:
order = strides2order( strides );
console.log( 'Strides: %s. Order: %s.', strides.join( ',' ), order );
}
```
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